Liquid-ring gas pumps



Jan. 11, 1966 u. SEGEBRECHT 3,228,587

LIQUID-RING 'GAS' PUMPS Filed Oct. 14, 1963 5 4 Sheets-Sheet 1 Jan. 11,1966 u sEGEB Ec 3,228,587

LIQUID-RING GAS PUMPS Filed Oct. 14, 1963 4 Sheets-Sheet 2 Jan. 11, 1966u. SEGEBRECHT 3,223,587

LIQUID-RING GAS PUMPS Filed Oct. 14, 1963 4 Sheets-Sheet 3 United StatesPatent 3,228,587 LIQUID-RING GAS PUMPS Udo Segebrecht, Itzehoe,Holstein, Germany, assignor to Siemen & Hinseh rn.b.H., Itzehoe,Holstein, Germany Filed Oct. 14, 1963, Ser. No. 315,759

Claims priority, application Germany, Oct. 17, 1962,

3 Claims. (Cl. 230-44) This invention relates to a liquid-ring gas pumphaving seated on a shaft two impellers, the working spaces of which onthe periphery and on both front sides of each impeller are formed bystationary casing parts.

In such pumps the two impellers can be connected in series so that atwo-stage pump results, or they can be connected in parallel in aone-stage pump.

If the two impellers are connected in series, then in conventionalmanner the cross current principle is applied. This means that on oneside of the pump on the suction cover the suction branch is arranged andon the other end the pressure cover provided with a pressure branch islocated. The medium flows over the suction branch and the casing coveron the suction side to the first stage and arrives in an intermediatecasing which is arranged between the two stages, flows from there to thesecond stage and leaves the latter through the pressure cover to apressure branch. Thus, in the pump on both sides parts of the casing arelocated which take care of the supply and discharge of the medium andbetween the two stages a casing part is arranged which serves forconducting the medium from the first to the second stage.

According to a further known embodiment, the entire supply and dischargeof the medium conveyed takes place over a distributing member which islocated between the two stages. In comparison with the first embodimentdescribed above, this pump has the advantage of having a shorterstructure. However, the intermediate distributing casing has a rathercomplicated structure and it is difficult and expensive to produce it bycasting, especially if the stages are not only single-acting, butdouble-acting.

In the parallel connection of two impellers in a pump it is possible toarrange the two impellers directly sideby-side and to arrange admissionon both sides. The impeller contains in this case in the middle aseparating wall which continues in the casing radially outside of theimpeller. Through the gap between the separating wall of the impellerand the separating wall of the casing, a connection is formed betweenthe working chambers of the two impellers, so that in this case the twoimpellers can be connected in fact in parallel only. A furtherpossibility of connecting in parallel two impellers in a pump consistsin that the entire supply and discharge of the medium conveyed iscarried out over a distributing member arranged between the two stages.In the same manner as in the case of impellers connected in series, suchdistributing casing would have a rather complicated structure and wouldbe correspondingly expensive.

The main object of the present invention is to provide a pump having twoimpellers and being as simple as possible in its construction, the twoimpellers being adapted to be connected in series as well as inparallel, without the necessity of substantial changes and with the useof parts which are as equal as possible.

This object is attained according to the present invention by arrangingin a liquid-ring gas pump having two impellers arranged side-by-side,between the two impellers a casing wall being arranged, which extends upto about the pump shaft. The supply of the media conveyed to and fromthe conveying spaces takes place only over the casing covers on thesuction side and pressure side of the pump. Thereby, it is irrelevantwhether the guiding ice of the medium conveyed to both stages ifconnected in parallel or from the first to the second stage if connectedin series, is carried out through channels cast in the pump casing or bymeans of tubes suitably arranged outside the casing.

It is of particular advantage to use channels cast-in in the casingparts, i.e. channels for connection in series as well as channels forparallel connection of the stages. By providing suitable recesses in thecontrol discs certain channels are opened in each case so that variousconnections of the impellers are attained.

It is also of particular advantage in the present pump construction, toconnect the stages relative to each other in such manner that a strainon the shaft in radial direction does not occur, or is extensivelycompensated for. If a complete removal of the load from the shaft isdesired, both impellers should be designed double-acting. In this casetoo, the two working rooms of each impeller can be also connectedparallel or in series.

In view of the fact that in case of a connection in series aconsiderable pressure drop may be present between the two stages, it isproposed according to the present invention to arrange a simple sealingbetween the two stages in the casing wall, in order to avoid losses.

Due to its short, compact structure, the pump is suitable for manyapplications in which such structure is preferred, particularly when thepump is combined with a permanent magnetic drive or with a canned motor(Sp altrohr-motor) The appended drawings illustrate by way of exampleand without limitation a best way for carrying out the invention.

In the drawings FIG. 1 illustrates a pump according to the invention infront view;

FIG. 2 is a sectional view of the pump along line AA in FIG. 1;

FIG. 3 is a top view of the pump according to FIGS. 1 and 2; therebyboth stages are connected in parallel by a corresponding arrangement bymeans of bypass P p FIG. 4 illustrates a pump according to FIG. 1, inwhich the two stages are connected in series by means of a pipe arrangedon the outside;

FIGS. 58 illustrate a modified embodiment of the invention, in which thediverting conduits are channels cast in the pump housing. The referencesymbols in FIGS. 58 correspond to those used in FIGS. 1-4, whileadditional reference symbols 2228 have been assigned to the innerdiversions;

FIG. 6 is a section along line AA in FIG. 5, while FIGS. 7 and 8 aresections along line BB in FIG. 5, FIG. 7 illustrating a connection ofthe two stages in parallel and FIG. 8 a connection in series;

FIG. 6 illustrates a parallel connection of the two stages.

In the various figures identical parts are denoted by the same referencesymbols.

Referring now to the drawings in detail, reference symbol 1 denotes thesuction branch and 2 denotes the pressure branch of the wide stage, inthe head member or means A, 3 denotes the suction branch and 4 thepressure branch of the narrow stage, in the opposing head member ormeans B. The impellers 5 and 6 are arranged on the shaft 7 and thesealing or packing of the passing of the shaft in outward direction isbrought about by the stuffing boxes 8, 8. The control disc 9 providedwith the sucking slot 10 and the pressure slot 11 belongs to the widestage of the pump and the control disc 12 provided with the suction slot13 and the pressure slot 14 belongs to the narrow stage of the pump.Between the two stages or steps a separating wall 15-which extends up tothe shaft 7is arranged and'coatainspmkm or sealing means 16 providedtherein.

The medium to be conveyed by the pump flowsif the stages are connectedin seriesaccording to FIG. 4, first through the suction branch 1 intothe suction space of the wide stage, passes through slot 10 into thecells of the impeller and leaves the latter through the pressure slot 11Through the branch 2, it passes into the by-pass pipe 17 and from therethrough the branch 3 and sucking slot'13 into the cells of the impeller6 of the second stage. It leaves the latter through the pressure slot14- and pressure branch 4 into the pressure conduit.

If the two stages are connected in parallel according to FIG. 3, themedium to be conveyed is introduced through branch 18 of tube 19 intobranches 1 and 3 of the two stages. The medium flows through the stagesin corresponding analogy to the above description of the connection inseries and passes through branches 2 and 4 into tube 20 and from therethrough 21 into the pressure conduit of the pump.

As already mentioned above, the supply of gas to both stages in the caseof connection in parallel, and the guiding of gas from the first to thesecond stage in the case of connection in series, can be also effectedthrough channels which are cast integrally into the casing. 'In thismodification it is merely necessary to replace the tubes 17, 19 and 20(see FIGS. 3 and 4) by corresponding channels located in the housing.

In the embodiment shown in FIG. 6, in the case of parallel connection,the medium to be conveyed enters through suction branch 1, in the headmember or means A of the pump into the suction space of the wide stageand through the bore 22 of the disc 9, 'the housing channel 28 and bore24 in control disc'12, the suction space of the narrow stages, as shownin FIG. 7. The conveyed medium discharged through pressure slits 11 and14 of the wide and narrow stages, respectively, passes to the pressurespaces of these stages and, from there, directly to the branch 4 andthrough bore 23 in the control disc 9, the housing channel 27 and bore25 in control disc 12 to branch 4, which is located in the opposing headmember or means B. i

In connecting the stages in series, as illustrated in FIG. 8, there areno bores 23 and 22 in control disc 9, but a bore 26 is provided for. Themedium conveyed follows thereby the following path:

Through the branch 1 the medium passes to the suction space of the widestage and over the suction slit "10 to the cells of impeller 5. Throughthe pressure slit 11 the medium passes to the pressure space of thefirst stage and through the bore 26 to the housing channel 28 and thebore 24 to the suction space of the second stage. From here the mediumflows through suction slit 13 to the cell of impeller 6 and passesthrough pressure slit 14 of this stage through the pressure space to thebranch 4 of the pump.

Thus, the parallel and the series connection can be brought about bysimple corresponding bores in the control disc 9. It will be understoodthat the channels can be cast in the housing not only on top, butarranged also at any'desired other place. If desired, the channels 27,28 can be operated in the pump by regulating devices which are locatedoutside of the pumps, so that the parts of the pump have entirely equalappearance.

What is claimed is:

1. A liquid-ring gas pump comprising a stationary housing includingopposing head means, a stationary wall means positioned between the headmeans and defining a pump chamber, a shaft rotatably extending throughthe chamber and sealingly and rotatably extending through the opposinghead means, said stationary wall means including a side wall meansarranged axially of the shaft and a first and a second stationarycontrol disc, said discs being structurally associated with the sidewall means and extending transversely thereof and of the shaft andspaced apart along the 'axis of the shaft, said shaft passing throughthe discs, an imperforate partition fixed transversely between the wallmeans and having only a single transverse opening through which theshaft passes, sealing means between the shaft and the partition, saidpartition being interposed between the discs and disposed parallelthereto in spaced relation with the discs along the axis of the shaft todivide the chamber into two separate and independent chamber sections,two separate and individual impellers fixedly mounted on the shaft anddisposed in spaced relation along the axis of the shaft, one

of said impellers being operatively disposed in one of the chambersections and the other of said impellers being operatively disposed inthe other of said chamber sections, inlet means and outlet means for theconveyed medium structurally associated with the head means outwardly ofthe discs, said discs having passages for the conveyed medium, and meansassociated with the head means and associated with the chamber sectionsfor selectively connecting said impellers in a two-stage series pumpoperation and connecting said impellers in a parallel one-stage pumpoperation.

'2. The invention of claim 1, wherein said side wall means ofthe'stationary wall means constitutes a connecting side wall between theopposing head means and said last means includes external pipingstructurally connected to the head means and in flow connection with theinlet and outlet means.

3. The invention of claim 1,-wherein said head means are connected byaside wall and said side wall means of 'the stationary wall means isdisposed within the side wall and said last means includes the provisionof internal castin channels in the side wall in flow connection with theinlet and outlet means.

References Cited by the Examiner UNITED STATES PATENTS 1,233,581 7/1917Johnston 23079 1,699,327 1/ 1929 Durdin 23079 1,847,586 3/1932 Adams23079 1,847,587 3/1932 Adams 23079 2,364,370 12/ 1944 Jennings 230793,108,738 10/ 1964 Luhmann 23079 3,154,240 10/1964 Jennings 23079FOREIGN PATENTS 1,057,284 5/ 1959 Germany.

869,170 5/ 1961 Great Britain. 571,477 6/1958 Italy. 150,182 3/1955Sweden.

DONLEY J. STOCKING, Primary Examiner.

LAURENCE V. EFNER, Examiner.

1. A LIQUID-RING GAS PUMP COMPRISING A STATIONARY HOUSING INCLUDINGOPPOSING HEAD MEANS, A STATIONARY WALL MEANS POSITIONED BETWEEN THE HEADMEANS AND DEFINING A PUMP CHAMBER, A SHAFT ROTATABLY EXTENDING THROUGHTHE CHAMBER AND SEALINGLY AND ROTATABLY EXTENDING THROUGH THE OPPOSINGHEAD MEANS, SAID STATIONARY WALL MEANS INCLUDING A SIDE WALL MEANSARRANGED AXIALLY OF THE SHAFT AND A FIRST AND A SECOND STATIONARYCONTROL DISC, SAID DISCS BEING STRUCTURALLY ASSOCIATED WITH THE SIDEWALL MEANS AND EXTENDING TRANSVERSELY THEREOF AND OF THE SHAFT ANDSPACED APART ALONG THE AXIS OF THE SHAFT, SAID SHAFT PASSING THROUGH THEDISCS, AN IMPERFORATE PARTITION FIXED TRANSVERSELY BETWEEN THE WALLMEANS AND HAVING ONLY A SINGLE TRANSVERSE OPENING THROUGH WHICH THESHAFT PASSES, SEALING MEANS BETWEEN THE SHAFT AND THE PARTITION, SAIDPARTITION BEING INTERPOSED BETWEEN THE DISCS AND DISPOSED PARALLELTHERETO IN SPACED RELATION WITH THE DISCS AND DISPOSED THE AXIS OF THESHAFT TO DIVIDE THE CHAMBER INTO TWO SEPARATE AND INDEPENDENT CHAMBERSECTION, TWO SEPARATE AND INDIVIDUAL IMPELLERS FIXEDLY MOUNTED ON THESHAFT AND DISPOSED IN SPACED RELATION ALONG THE AXIS OF THE SHAFT, ONEOF SAID IMPELLERS BEING OPERATIVELY DISPOSED IN ONE OF THE CHAMBERSECTIONS AND THE OTHER OF SAID IMPELLERS BEING OPERATIVELY DISPOSED INTHE OTHER OF SAID CHAMBER SECTIONS, INLET MEANS AND OUTLET MEANS FOR THECONVEYED MEDIUM STRUCTURALLY ASSOCIATED WITH THE HEAD MEANS OUTWARDLY OFTHE DISCS, SAID DISCS HAVING PASSAGES FOR THE CONVEYED MEDIUM, AND MEANSASSOCIATED WITH THE HEAD MEANS AND ASSOCIATED WITH THE CHAMBER SECTIONSFOR SELECTIVELY CONNECTING SAID IMPELLERS IN A TWO-STAGE SERIES PUMPOPERATION AND CONNECTING SAID IMPELLERS IN A PARALLEL ONE-STAGE PUMPOPERATION.